A large number of electrical connectors and counter-connectors are known that transmit electrical currents, voltages, signals and/or data with a large range of currents, voltages, frequencies and/or data rates. In the low, medium, or high voltage and/or current ranges, and especially in the motor vehicle industry, connectors must ensure permanently, repeatedly and/or, after a comparatively long service life, transmission of electrical power, signals and/or data without delay in warm, possibly hot, polluted, humid and/or chemically aggressive environments. Due to a wide range of applications, a large number of specially configured connectors are known.
Connectors or their housings can be installed at an electrical cable, a wire, a cable harness, or an electrical unit or device such as at/in a housing, at/on a leadframe, at/on a printed circuit board etc., of an electrical, electro-optical, or electronic component. A connector located at a cable, a wire, or a cable harness is known as a connector or a plug. A connector located at an electrical component is known as a counter-connector unit, often referred to as a receptacle or header.
Connectors must ensure perfect transmission of electrical signals and/or electrical power, wherein connectors corresponding with one another usually have fastening or locking arrangements for long-term but usually releasable fastening or locking of the connector at/in the counter-connector. Further, an electrical connecting unit having a contact device, such as a contact element, a ferrule, a terminal, or a shield contact sleeve, or a contact unit, must be received securely therein. In an assembled cable, such a connecting unit can be provided as a connector without a housing. Since the housings of the connectors are usually subject to a certain standardization, such as the FAKRA standard, the most important dimensions of the housings have the same dimensions across different manufacturers. Continuous efforts are being made to improve electrical contact devices, contact units, connecting units, connectors and assembled cables to make them smaller and more cost-effective.
Electromagnetically shielded twin-axial cables for high-speed differential signal transmission deviate from a circular cross-sectional geometry that is typical for cables and have an at least partially oval, for example elliptical, cross-sectional geometry. In this case, two electrical inner conductors of the twin-axial cable are surrounded by an electrical outer conductor such as a shielded film. Either the shield or an entire cross-sectional geometry of the twin-axial cable has an oval shape.
In order to obtain a small plug connection, an electromechanical interface of an electrical connecting unit for the twin-axial cable also has an oval cross-sectional geometry. A cross-sectional geometry of a crimping section of a cable has a circular cross-section in the prior art. Typical contact devices for crimping for twin-axial cables also have a circular cross-sectional geometry in a crimping section. A shield contact sleeve for a twin-axial cable which results therefrom, for example, requires a transition from oval, in an electrical contact section, to circular and optionally back to oval at an outer conductor crimping section. Such a transition is located at a critical point in a plug connector, where a comparatively narrow distance of the inner conductor of the twin-axial cable transitions into a wider division of the contact devices or contact units of the connector. Such a transition leads to a barely compensatable discontinuity in the impedance in the prior art, as shown in FIG. 12, which delimits a maximum usable frequency of such a plug connector, in particular in the full duplex mode of a related twin-axial cable.